The Research And Development On Grid Converter In Direct-driven Wind Turbine

Wind energy as a clean and renewable energy, the rapid development of the world's new energy, one of the most important direction of development. This dissertation is a part of the project of developing MW-level Wind Energy Conversion System which is a key 863 program. That is major scientific and technological special in Hunan Science and Technology Agency Eleventh-five program. 2MW direct-drive type permanent magnet synchronous motor variable speed constant frequency wind power converter system is introduced. 2MW direct-drive type permanent magnet synchronous motor variable speed constant frequency wind power converter system to study the network-side converter control method and system engineering.The first, this article introduced the purpose and significance of wind power technology. And then the technology of wind power was introduced at home and abroad research. And analysis of wind power generation technology Project background. Direct-drive wind power generation wind power is becoming today's hot technology. The direct-drive wind power grid converter system is researched and designed in this paper.Converter systems grid connected with AC - DC - AC in the direct-drive wind turbine. Focus on the permanent magnet direct-drive wind power generation and network converter to do an in-depth analysis in dual PWM converter. A two-phase rotating coordinate system (d-q) of the mathematical model is established. In the grid-side converter, the proposed a variety of control and described a variety of control advantages and disadvantages. Focuses on the voltage-oriented vector-based (VOC) control through the establishment of the system transfer function, calculated in the dual closed-loop system voltage regulator and current regulator parameters P and I parameters. Taking into account the cost savings and reduction of interference caused by the sensor problem, non-voltage control sensor was proposed. Analysis of the control principle and the realization of the way and give simulation results under the MATLAB / Simulink.Wind farm environment is generally bad and the speed of change is uncertain, therefore generating a greater output voltage fluctuations. The regulator generally more difficult to adapt to changes in the system, but the smart regulator has excellent characteristics such as self-study, self-adaptive. Therefore the fuzzy PI regulator is used as a voltage regulator ring in order to improve the performance of the system in this paper. Simulation results show that the fuzzy PI regulator has a good performance.The high speed integrated control chip DSP2808 is the core of control. According to control flow chart,the hardware and software are designed, to build an experimental platform, which implementation of the control panel signal acquisition, operation, fault detection, and circuit-driven features. At the mean time, an experiment platform of wind energy conversion system is constructed and the experimental waveforms are presented and analyzed in this paper.